I dont even know where did this decision of model come from.
For the exploration, i can explicitly change the model in settings>Models>Explore Subagent Model
but i cant find any place to change the model for the subagent automatically spawned for code writing/implementing.
The closest settings I could find to change this is in settings>Agents>Default Model. But i still cant choose specific model, only Cursor Default or Last Used, I have tried to change this but it didnt work (I never explicitly used Opus before)
There isn’t a setting yet to change the model for the built-in General Purpose subagent. A couple of nearby controls are easy to mix up:
Explore Subagent Model only controls the Explore subagent (codebase search and research). It does not apply to general-purpose or implementation subagents.
Agents → Default Model only chooses whether new chats start on Cursor Default or Last Used. It does not set the model for subagents, which is why changing it didn’t affect the Opus 5 High run.
When the main agent launches a general-purpose subagent, it can choose a model for that task. It chooses the model that it thinks would be best suited for the task and is available for it to use. That is why you can see Opus 5 High on that card even if you haven’t used Opus yourself in the parent chat.
Until a dedicated picker exists, these are the best options:
Turn off models you don’t want available to use as Subagents under Cursor Settings → Models. In the desktop app that can shrink what the agent is offered, but it is not a 100% guaranteed block. In my brief tests, it does work successfully.
Custom subagent with a model in frontmatter. Add a markdown file under .cursor/agents/ (this project) or ~/.cursor/agents/ (all projects). Use model: inherit to keep it on the parent chat’s model, or pin a specific model ID. Details: Subagent model configuration
Add a rule asking the agent to keep implementation subagents on the same model as the parent chat (for example, Grok 4.5) unless you explicitly ask otherwise. Rules guide the agent. They are not a hard lock. See Rules.
I ran this test below after disabling all models in Cursor Settings except for Cursor Grok 4.5 and Composer 2.5, and it was effective in limiting the models available to the subagent. While not a guarantee, this is a good place to start.
